Even ahead of the launch, our partner site CNET reported on many of the most significant new features. Here are some of the upgrades you'll see in iOS 9.3.

Night Shift

For night owls who may find their sleep disturbed by the bright blue light emitted by their laptop and smartphone screens, Night Shift might be their favorite feature of the new iOS. The feature uses your phone's clock and geolocations to determine when the sun sets in your given location. Once it gets darker out, your phone's display colors shift to warmer hues like red, orange, and yellow.

For You

For You, the new news app will provide articles and information tailored to your interests.
Apple

All the news that's fit to curate -- For You, Apple's improved news app, will provide information that is tailored to your interests. The feature will suggest trending topics and give you "editor's picks" of articles and stories you should be checking out. Video stories can be played right from your newsfeed.

Health

The Health app gives you access to more health and wellness metrics.
Apple

The updated Health app gives users access to more helpful health and wellness data. For those looking for more ways to track their health and wellness on their phones, categories like Weight and Workouts in the improved Health feature will have a slider menu that reveals useful third-party apps. Health also displays users' exercise and activity data and goals collected from your Apple Watch.

CarPlay

A woman touches the display inside a Volvo during the media day ahead of the 84th Geneva Motor Show, March 4, 2014.
REUTERS/Arnd Wiegmann

CarPlay is being updated to include "New and For You" from Apple Music -- which provides songs, artists, and albums selected by experts. There are also selections of tunes to give you background music while you drive that are based on your preferences. The Nearby feature found in Maps also makes it easier for drivers to find convenient gas stations or restaurants on your commute or road trip.

Notes

Now your Notes will be more secure with password and fingerprint protection.
Apple

You might want to make sure the information you type into your iPhone's Notes feature remains private and secure. With the iOS 9.3 update, Apple is adding password and fingerprint protection to the Notes app. Your notes can also now be sorted alphabetically as well as by the date of creation and date of modification.

Education

The new iOS is giving teachers new educational tools for the classroom.
Apple

One Apple product that has become very popular in classrooms is the iPad. The new iOS 9.3 operating system includes new educational tools that should prove useful to teachers. The Classroom app allows teachers to plan lessons and track student progress. Apple IDs for education are also going to be introduced that can be managed by school administrators. Students will also be able to log in with their individual accounts on shared iPads.

Apple Watch support

A trio of Apple Watches.
Apple

iOS 9.3 will enable support for more than one connected Apple Watch per iPhone.

3D Touch

iPhone 6S and 6S Plus will get more 3D Touch shortcuts.
REUTERS/Robert Galbraith

Now that iPhone 6S users have gotten a chance to get used to 3D Touch, the taptic feature that responds differently to varying degrees of pressure is going to be expanded. CNET reports there will be new 3D Touch shortcuts for the Weather, Settings, Health, App Store, iTunes Store and Compass apps on the iPhone 6S and 6S Plus.